Servoing mechanism for improved typewriter ribbon spooling

ABSTRACT

A web-spooling apparatus for winding a thin web on a core is constructed to control any tendency of the web to telescope. A drive roller rides on the periphery of the web as it winds the web on the core. The drive roller includes web-penetrating radial spikes and has a pair of flanges at the top and bottom which extend radially beyond the spikes and contact the edges of the web should the web tend to move axially off the core. The core is mounted on a spindle in such a way as to permit the core to yaw about the spindle. Contact between the web and a flange causes the core to be yawed about the spindle and thereby provides an angle of small magnitude between the core and web, thus causing the web to move axially in a direction opposite to its first such action, thereby tending to correct the telescoping condition.

United States Patent [72] Inventors David R. Cialone;

Clifford E. Herrick; George T. Slaughter, all of Lexington, Ky. [21]Appl. No. 51,233 [22] Filed June 30, 1970 [45] Patented Nov. 9, 1971[73] Assignee International Business Machines Corporation Armonk, NY.

[54] SERVOING MECHANISM FOR IMPROVED TYPEWRITER RIBBON SPOOLING 7Claims, 8 Drawing Figs.

[52] U.S. Cl 242/673, 242/65, 242/683, 197/151 [51] Int. Cl B65h 17/02,B65h 17/08 [50] Field of Search 242/673, 65, 68, 68.3, 66, 56, 56.2,57.1, 67.1; 197/151, 175

[56] References Cited UNITED STATES PATENTS 1,017,984 2/1912 Martin242/67.3

Primary Examiner-Stanley N. Gilreath Assistant Examiner-Gregory A.Walters Attorneys-Hamlin and Jancin and E. Ronald Coffman ABSTRACT: Aweb-spooling apparatus for winding a thin web on a core is constructedto control any tendency of the web to telescope. A drive roller rides onthe periphery of the web as it winds the web on the core. The driveroller includes web-penetrating radial spikes and has a pair of flangesat the top and bottom which extend radially beyond the spikes andcontact the-edges of the web should the web tend to move axially off thecore. The core is mounted on a spindle in such a way as to permit thecore to yaw about the spindle. Contact between the web and a flangecauses the core to be yawed about the spindle and thereby provides anangle of small magnitude between the core and web, thus causing the webto move axially in a direction opposite to its first such action,thereby tending to correct the telescoping condition.

PATENTEDHUV 9 I911 SHEET 1 [1F 3 b 2 m F INVENTORS DAVID R. CIALONEcummn E. HERRICK ,JR.

GEORGE T. SLAUGHTER BY MQMM ATTORNEY.

BACKGROUND OF THE INVENTION This invention relates to typewriter ribbonsand more particularly to a ribbon takeup spool device.

The development of typewriter ribbons is tending toward ribbons whichafford substantially increased yields and hence longer intervals betweenribbon replacement. Such improvedyield ribbons necessarily involve theuse of much thinner ribbons than those which are common in presentcommercial use. The fragility of such thin, high-yield ribbonsnecessitates ribbon-handling mechanism which are designed for minimumstress, because such thin ribbons typically exhibit reduced tensilestrength, high compliance, and unusually marked changes in suchproperties with temperature and humidity.

Mechanical arrangements adapted to unspooling, bringing the ribbon thethe printing position, and driving the ribbon have been disclosed, forexample, in US. Pat. application Ser. No. 752,096, filed July 16, 1968by W. Golf and A. H. Caudill.

Thin ribbons such as the polymer matrix ribbons described, for example,in U.S. Pat. No. 3,413,184 pose an additional problem in takeupspooling. Because of the extreme length of the ribbon to be taken up,together with compliance characteristics which prohibit the use ofedge-guiding techniques effective with more rigid or thicker ribbons,considerable difficulty is experienced in the takeup spooling operation.A characteristic difficulty is known as telescoping. If ribbon that iscontained in a ribbon cartridge telescopes, i.e. moves axially duringwinding, it will bind tightly against the top or bottom of the cartridgeand causes either excessive stress on the drive mechanism or ribbonadvance failure or both.

There is, therefore, a need for a takeup mechanism which will insureaccurate ribbon tracking under all conditions.

BRIEF DESCRIPTION OF THE INVENTION We have now found a servoing schemewhich is effective in improving ribbon tracking.

In accordance with this invention there is provided an apparatus forwinding a thin ribbon on a core and controlling the telescoping of theweb on the core, comprising a spiked drive roller which contacts theface of the web wound on the core and feeds the web to the core. Thedrive roller and core are mounted to move apart as the diameter of theweb on the core increases. The drive roller is located to contact theweb in the hemicircle defined between the point where the web enters thecore and about 180 in the direction of rotation of the core. The core ismounted for rotation by means which permits the core to yaw about thenominal axis of rotation. The drive roller includes guide flanges at itstop and bottom which are adapted to contact the edges of the web shouldthe web begin to telescope on the core. Contact between the web and oneof the guide flanges causes the core to yaw about the nominal axis ofrotation and assume a new axis of rotation which is related to thedirection of ribbon travel in such a way that the telescoping conditionis arrested and corrected.

The foregoing and other objects, features and advantages of theinvention will be apparent from the following more particulardescription of preferred embodiments of the invention as illustrated inthe accompanying drawings.

DESCRIPTION OF THE DRAWINGS FIG. 1a is a schematic top view of anembodiment of the invention in a first condition.

FIG. lb is a schematic elevational view with parts broken away of anembodiment of the invention in the condition illustrated in FIG. la.

FIG. 2a is a schematic top view of the embodiment of the inventionillustrated in FIGS. 1a and lb in a broken condition.

FIG. 2b is an elevational view with parts broken away of the embodimentof the invention in the condition shown in FIG. 20. FIG. 3a is aschematic top view of the embodiment of the invention illustrated inFIGS. 1a and 1b in a third condition.

FIG. 3b is an elevational view with parts away of the embodiment of theinvention in the condition illustrated in FIG. 3a.

FIG. 4 is an exploded isometric view with parts broken away of anembodiment of the invention including a ribbon cartridge.

FIG. 5 is an elevational view partially in section with parts brokenaway of the cartridge illustrated in FIG. 4.

- DETAILED DESCRIPTION FIGS. la and 1b, 2a and 2b and 3a and 3billustrate an embodiment of the invention at several stages in the,spooling process. The angular deflections are somewhat exaggerated forthe sake of illustration. As shown in FIGS. la and lb ribbon I1 isdirected around guide roll or post 10 to the periphery of takeup core 14which is mounted on a takeup spool stud 13 with a clearance of about0.002-0.004 in. such that core 14 can yaw about stud 13. The surface ofribbon 11 would on takeup core 14 is penetrated by spikes 15 on acylindrical drive member or roller 16 having a pair of flanges 17 and 19that extend radially outward beyond the spikes 15. The drive roller 16is located to contact the ribbon at some point in a hemicircle beginningat where the ribbon contacts the wound portion of the ribbon on the coreand continuing around in the direction of rotation of the core.

FIG. lb illustrates a first condition of the takeup core 14 and ribbon11. Assuming that for various reasons (parts misalignment, baggy ribbonedge, or other mechanism characteristics) the takeup core 14 and ribbon11 bear the relationship that takeup core 14 is tilted counterclockwise.Because of the tilt, ribbon 11 will move toward the bottom flange 17 ofthe drive roller until edge 18 contacts flange 17. This downwardtendency will result because friction between the ribbon web 11 and thespooled ribbon l2 acts to maintain the relative vertical relationship ofthe point of contact between web 11 and spooled ribbon 12. At this timethe portion 12 of the ribbon wound on the core will be as is shown inFIGS. 2a and 2b with the contact between edge 18 and flange 17 causingthe core 14 to yaw about stud 13 to a position where the axis 20 of thecore 14 is moved to the vertical. The ribbon will now wind parallel tothe edge of the core 14.

A continuation 'of the downward telescoping of the ribbon 12, for anyreason, would act to tilt the axis of the takeup core beyond thevertical, causing the ribbon 11 to move upwardly as is shown in thecondition illustrated in FIGS. 3aand 3b. In this condition, the tiltproduces an upward tendency through the action of friction tending tomaintain the vertical relationship of first contact between web 11 andspool 12. This action tends to restore the ribbon to the center positionon core 14. In the event that overcompensation occurs, so that ribbon 11moves to the top flange 19, the upward motion is terminated by the samerestoring mechanism described above, operating in the opposite sense.

Although the wound portion 12 of ribbon 11 may have a somewhatnonparallel configuration on takeup core 14, the flanges l7 and 19 ondrive roller 16 confine the ribbon and prevent the ribbon from bindingagainst the adjust mechanism such as the walls of a cartridge in whichthe ribbon is enclosed. Excessive binding forces will not be encounteredbecause the drive roller 16 and flanges 17 and 19 are continually movingoutwardly from the takeup core so that there'are no cumulative forcesbetween the flanges and the wound portion 12 on core 14 due to previoustelescoping.

FIGS. 4 and 5 illustrate an embodiment of the invention contained in aneasily mountable, self-contained ribbon cartridge 27 having a supply 20of ribbon 21 on a supply spool 23. The cartridge and ribbon advancemechanism are shown for example, in application Ser. No. 752,096 filedJuly I6, 1968. Cartridge 27 as a top portion 26 and a bottom portion 28and is mounted on the print carriage 22 of a typewriter and held inplace by clips 30 at each end which enter slots 32. The ribbon exitsfrom a slot (not shown) in the sidewall 25 of cartridge 27 and isadapted to be passed through the ribbon guide mechanism (not shown) atthe print point of the typewriter and then back into cartridge 27through a second slot 29, around ribbon guide post 31 and then to theperiphery of takeup core 24. The drive roller 35 enters the cartridge 27through an elongated curved slot 38, as cartridge is engaged onto theribbon drive mechanism. Drive roller 35 is attached to and adapted to beincrementally rotated by the printing machine ribbon advance mechanism.Drive roller 35 has a series of spikes 36 on its driving surface forpenetrating ribbon 21. Drive roller 35 is urged into contact with spoolportion 34 by a spring (not shown) and is permitted to move away fromthe takeup core 24 as the diameter of the wound ribbon increases. Theshape of slot 38 permits the drive roller 35 to move without contactingthe cartridge 27. Flanges 37 and 39 on the top and bottom of driveroller 35 are adapted to contact the edges of ribbon 21 if the ribbontends to telescope on takeup core 24. Core 24 as illustrated in FIG. isloosely mounted on stud 33 and is loosely held for rotation between thetop wall 26 and the bottom wall 28 of cartridge 27 in a mannerpermitting core 24 to rotate and yaw about stud 33. The servoingoperation of the apparatus is as is described in the embodiment shown inFIGS. la and lb, 2a and 2b, and 3a and 3b with the ribbon contacting thetop or bottom walls 26 and 28 of cartridge 27. Therefore, binding,tearing or folding of the ribbon due to the telescoping on the core isavoided.

The foregoing described an improved typewriter ribbonspooling apparatusemploying a servoing mechanism without which it has been foundimpossible to reliably wind relatively fragile ribbon webs on takeupcore contained in a cartridge without excessive binding forces beingencountered.

While the invention has been practically shown and described withreference to preferred illustrative embodiment thereof, it will beunderstood by those skilled in the art that various changes in form anddetail may be made therein without departing from the spirit and scopeof the invention as defined by the aforegoing claim.

We claim:

1. Apparatus for winding a web on a core comprising:

a rotatable drive member which is mounted to contact the periphery ofthe web wound on the core and feed the web to the core,

mounting means to mount the drive member and core such that the saiddrive member and core move apart as the diameter of the web wound on thecore increases,

means for mounting said core for rotation so as to permit the core toyaw about its nominal axis of rotation, and

guide means mounted at the top and bottom of said drive member, saidguide means being adapted to contact the edges of the web if the webshould telescope on said core and being so disposed relative to the corethat contact between said web and one of said guide means will causesaid core to yaw about said axis in a direction tending to correct thetelescoping condition.

2. Winding apparatus as defined in claim 1 wherein said drive membercomprises a roller having radially extending spikes therein forpenetrating the web wound on said core, and said guide means extendradially outwardly of said roller beyond said spikes.

3. Apparatus for winding a web on a core comprising:

a rotatable drive member which is mounted to contact the periphery ofthe web wound on the core at a point in a hemicircle defined by thepoint where the web contacts the wound portion and a point about fromwhere the web contacts the wound portion in the direction of rotation ofthe core and feed the web to the core,

mounting means to mount the drove member and core such that the saiddrive member and core move apart as the diameter of the web wound on thecore increases,

a spindle for mounting said core so as to permit the core to yaw aboutsaid spindle, and

a pair of flanges on said drive member located at the top and bottom,said flanges being adapted to contact the edges of the web if the webshould telescope on said core such that contact between said web and oneof said flanges will cause said core to yaw about said spindle andthereby correct the telescoping condition.

4. Winding apparatus as defined in claim 3 wherein said drive membercomprises a roller having radially extending spikes thereon forpenetrating the web wound on said core, and said pair of flanges extendradially outwardly of said roller beyond said spikes.

5. An inked ribbon feed mechanism including:

a rotatable mounted supply spool; a spindle;

takeup spool loosely mounted to yaw on said spindle.

an inked ribbon having one end attached to said supply spool and itsother end attached to said takeup spool;

and means to engage said ribbon on said takeup spool to advance saidribbon from said supply spool to said takeup spool past a printingposition, said engaging means having sufficient traction with saidribbon to provide the total driving force for winding said ribbon onsaid takeup spool and said engaging means having guide means located atthe top and bottom of said engaging means, said guide means beingadapted to contact the edges of said ribbon if the ribbon shouldtelescope relative to said core to correct the telescoping condition.

6. The mechanism according to claim 5 in which:

said engaging means is a drive roller having pointed projections thereonfor penetrating said inked ribbon on said takeup spool to providepositive engagement therewith and with sufficient traction to providethe total driving force of said ribbon, said drive roller havingcircular flanges located at the top and bottom of said roller andextending radially outward of said pointed projections,

and resilient means to constantly urge said projections on said driveroller into said inked ribbon irrespective of the diameter of said inkedribbon on said takeup spool.

7. The mechanism according to claim 6 including:

a base plate;

a cartridge, said cartridge having a top wall, a bottom wall and asidewall connecting said top and bottom walls removably mounted on saidbase plate; said supply spool being rotatably mounted in said cartridge;

said takeup spool being rotatably mounted in said cartridge;

said drive roller is supported by said base plate and extends through acurved slot in the bottom wall of said cartridge, and

said circular flanges are located between said top wall and said bottomwall of said cartridge.

1. Apparatus for winding a web on a core comprising: a rotatable drivemember which is mounted to contact the periphery of the web wound on thecore and feed the web to the core, mounting means to mount the drivemember and core such that the said drive member and core move apart asthe diameter of the web wound on the core increases, means for mountingsaid core for rotation so as to permit the core to yaw about its nominalaxis of rotation, and guide means mounted at the top and bottom of saiddrive member, said guide means being adapted to contact the edges of theweb if the web should telescope on said core and being so disposedrelative to the core that contact between said web and one of said guidemeans will cause said core to yaw about said axis in a direction tendingto correct the telescoping condition.
 2. Winding apparatus as defined inclaim 1 wherein said drive member comprises a roller having radiallyextending spikes therein for penetrating the web wound on said core, andsaid guide means extend radially outwardly of said roller beyond saidspikes.
 3. Apparatus for winding a web on a core comprising: a rotatabledrive member which is mounted to contact the periphery of the web woundon the core at a point in a hemicircle defined by the point where theweb contacts the wound portion and a point about 180* from where the webcontacts the wound portion in the direction of rotation of the core andfeed the web to the core, mounting means to mount the drive member andcore such that the said drive member and core move apart as the diameterof the web wound on the core increases, a spindle for mounting said coreso as to permit the core to yaw about said spindle, and a pair offlanges on said drive member located at the top and bottom, said flangesbeing adapted to contact the edges of the web if the web shouldtelescope on said core such that contact between said web and one ofsaid flanges will cause said core to yaw about said spindle and therebycorrect the telescoping condition.
 4. Winding apparatus as defined inclaim 3 wherein said drive member comprises a roller having radiallyextending spikes thereon for penetrating the web wound on said core, andsaid pair of flanges extend radially outwardly of said roller beyondsaid spikes.
 5. An inked ribbon feed mechanism including: a rotatablymounted supply spool; a spindle; takeup spool loosely mounted to yaw onsaid spindle. an inked ribbon having one end attached to said supplyspool and its other end attached to said takeup spool; and means toengage said ribbon on said takeup spool to advance said ribbon from saidsupply spool to said takeup spool past a printing position, saidengaging means having sufficient traction with said ribbon to providethe total driving force for winding said ribbon on said takeup spool andsaid engaging means having guide means located at the top and bottom ofsaid engaging means, said guide means being adapted to contact the edgesof said ribbon if the ribbon should telescope relative to said core tocorrect the telescoping condition.
 6. The mechanism according to claim 5in which: said engaging means is a drive roller having pointedprojections thereon for penetrating said inked ribbon on said takeupspool to provide positive engagement therewith and with sufficienttraction to provide the total driving force of said ribbon, said driveroller having circular flanges located at the top and bottom of saidroller and extending radially outward of said pointed projections, andresilient means to constantly urge said projections on said drive rollerinto said inked ribbon irrespective of the diameter of said inked ribbonon said takeup spool.
 7. The mechanism according to claim 6 including: abase plate; a cartRidge, said cartridge having a top wall, a bottom walland a sidewall connecting said top and bottom walls removably mounted onsaid base plate; said supply spool being rotatably mounted in saidcartridge; said takeup spool being rotatably mounted in said cartridge;said drive roller is supported by said base plate and extends through acurved slot in the bottom wall of said cartridge, and said circularflanges are located between said top wall and said bottom wall of saidcartridge.